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Very quick method of model recognition based on texture CRCs

Azorbix 03-03-2010

Very quick method of model recognition based on texture CRCs

Azorbix

Published on 03-03-2010 12:18 PM

Hey y'all, This is my first tutorial in a long time, so comment below and let me know what you think. Preable The worst ...

17 Comments

VAC:2 Analysis Cont:

wav

Published on 02-22-2010 07:19 PM

Categories:

Dissasembly

While being efficiently bored I decided to in my awesomeness continue messing around with VAC.

I took a whack at analyzing their scan decode/encode stuff whilst not in any true detail such as decoding it manually and such.

Perhaps my most interesting findings were:

Code:

13BE236E   8360 10 00           AND DWORD PTR DS:[EAX+10],0
13BE2372   8360 14 00           AND DWORD PTR DS:[EAX+14],0
13BE2376   C700 01234567        MOV DWORD PTR DS:[EAX],67452301
13BE237C   C740 04 89ABCDEF     MOV DWORD PTR DS:[EAX+4],EFCDAB89
13BE2383   C740 08 FEDCBA98     MOV DWORD PTR DS:[EAX+8],98BADCFE
13BE238A   C740 0C 76543210     MOV DWORD PTR DS:[EAX+C],10325476
13BE2391   C3                   RETN

Code:

13BE1C86   83EC 44              SUB ESP,44
13BE1C89   8B51 0C              MOV EDX,DWORD PTR DS:[ECX+C]
13BE1C8C   53                   PUSH EBX
13BE1C8D   56                   PUSH ESI
13BE1C8E   8B71 08              MOV ESI,DWORD PTR DS:[ECX+8]
13BE1C91   57                   PUSH EDI
13BE1C92   8B79 04              MOV EDI,DWORD PTR DS:[ECX+4]
13BE1C95   8BDA                 MOV EBX,EDX
13BE1C97   33DE                 XOR EBX,ESI
13BE1C99   23DF                 AND EBX,EDI
13BE1C9B   33DA                 XOR EBX,EDX
13BE1C9D   0318                 ADD EBX,DWORD PTR DS:[EAX]
13BE1C9F   8B11                 MOV EDX,DWORD PTR DS:[ECX]
13BE1CA1   8D9413 78A46AD7      LEA EDX,DWORD PTR DS:[EBX+EDX+D76AA478]
13BE1CA8   C1C2 07              ROL EDX,7
13BE1CAB   03D7                 ADD EDX,EDI
13BE1CAD   8BDE                 MOV EBX,ESI
13BE1CAF   33DF                 XOR EBX,EDI
13BE1CB1   23DA                 AND EBX,EDX
13BE1CB3   33DE                 XOR EBX,ESI
13BE1CB5   0358 04              ADD EBX,DWORD PTR DS:[EAX+4]
13BE1CB8   8B71 0C              MOV ESI,DWORD PTR DS:[ECX+C]
13BE1CBB   8DB433 56B7C7E8      LEA ESI,DWORD PTR DS:[EBX+ESI+E8C7B756]
13BE1CC2   8BDF                 MOV EBX,EDI
13BE1CC4   33DA                 XOR EBX,EDX
13BE1CC6   C1C6 0C              ROL ESI,0C
13BE1CC9   03F2                 ADD ESI,EDX
13BE1CCB   23DE                 AND EBX,ESI
13BE1CCD   33DF                 XOR EBX,EDI
13BE1CCF   0358 08              ADD EBX,DWORD PTR DS:[EAX+8]
13BE1CD2   8B79 08              MOV EDI,DWORD PTR DS:[ECX+8]
13BE1CD5   8DBC3B DB702024      LEA EDI,DWORD PTR DS:[EBX+EDI+242070DB]
13BE1CDC   C1CF 0F              ROR EDI,0F
13BE1CDF   03FE                 ADD EDI,ESI
13BE1CE1   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE1CE4   8BDE                 MOV EBX,ESI
13BE1CE6   33DA                 XOR EBX,EDX
13BE1CE8   23DF                 AND EBX,EDI
13BE1CEA   8B79 04              MOV EDI,DWORD PTR DS:[ECX+4]
13BE1CED   33DA                 XOR EBX,EDX
13BE1CEF   0358 0C              ADD EBX,DWORD PTR DS:[EAX+C]
13BE1CF2   8DBC3B EECEBDC1      LEA EDI,DWORD PTR DS:[EBX+EDI+C1BDCEEE]
13BE1CF9   C1CF 0A              ROR EDI,0A
13BE1CFC   037D F4              ADD EDI,DWORD PTR SS:[EBP-C]
13BE1CFF   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE1D02   897D FC              MOV DWORD PTR SS:[EBP-4],EDI
13BE1D05   8BFE                 MOV EDI,ESI
13BE1D07   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1D0A   237D FC              AND EDI,DWORD PTR SS:[EBP-4]
13BE1D0D   33FE                 XOR EDI,ESI
13BE1D0F   0378 10              ADD EDI,DWORD PTR DS:[EAX+10]
13BE1D12   8D9417 AF0F7CF5      LEA EDX,DWORD PTR DS:[EDI+EDX+F57C0FAF]
13BE1D19   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE1D1C   337D FC              XOR EDI,DWORD PTR SS:[EBP-4]
13BE1D1F   C1C2 07              ROL EDX,7
13BE1D22   0355 FC              ADD EDX,DWORD PTR SS:[EBP-4]
13BE1D25   23FA                 AND EDI,EDX
13BE1D27   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1D2A   0378 14              ADD EDI,DWORD PTR DS:[EAX+14]
13BE1D2D   8DB437 2AC68747      LEA ESI,DWORD PTR DS:[EDI+ESI+4787C62A]
13BE1D34   8B7D FC              MOV EDI,DWORD PTR SS:[EBP-4]
13BE1D37   33FA                 XOR EDI,EDX
13BE1D39   C1C6 0C              ROL ESI,0C
13BE1D3C   03F2                 ADD ESI,EDX
13BE1D3E   23FE                 AND EDI,ESI
13BE1D40   337D FC              XOR EDI,DWORD PTR SS:[EBP-4]
13BE1D43   0378 18              ADD EDI,DWORD PTR DS:[EAX+18]
13BE1D46   8DBC1F 134630A8      LEA EDI,DWORD PTR DS:[EDI+EBX+A8304613]
13BE1D4D   8B58 1C              MOV EBX,DWORD PTR DS:[EAX+1C]
13BE1D50   895D EC              MOV DWORD PTR SS:[EBP-14],EBX
13BE1D53   C1CF 0F              ROR EDI,0F
13BE1D56   03FE                 ADD EDI,ESI
13BE1D58   8BDE                 MOV EBX,ESI
13BE1D5A   33DA                 XOR EBX,EDX
13BE1D5C   23DF                 AND EBX,EDI
13BE1D5E   33DA                 XOR EBX,EDX
13BE1D60   035D EC              ADD EBX,DWORD PTR SS:[EBP-14]
13BE1D63   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE1D66   8B7D FC              MOV EDI,DWORD PTR SS:[EBP-4]
13BE1D69   8DBC3B 019546FD      LEA EDI,DWORD PTR DS:[EBX+EDI+FD469501]
13BE1D70   C1CF 0A              ROR EDI,0A
13BE1D73   037D F4              ADD EDI,DWORD PTR SS:[EBP-C]
13BE1D76   897D FC              MOV DWORD PTR SS:[EBP-4],EDI
13BE1D79   8BFE                 MOV EDI,ESI
13BE1D7B   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1D7E   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE1D81   237D FC              AND EDI,DWORD PTR SS:[EBP-4]
13BE1D84   33FE                 XOR EDI,ESI
13BE1D86   0378 20              ADD EDI,DWORD PTR DS:[EAX+20]
13BE1D89   8D9417 D8988069      LEA EDX,DWORD PTR DS:[EDI+EDX+698098D8]
13BE1D90   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE1D93   337D FC              XOR EDI,DWORD PTR SS:[EBP-4]
13BE1D96   C1C2 07              ROL EDX,7
13BE1D99   0355 FC              ADD EDX,DWORD PTR SS:[EBP-4]
13BE1D9C   23FA                 AND EDI,EDX
13BE1D9E   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1DA1   0378 24              ADD EDI,DWORD PTR DS:[EAX+24]
13BE1DA4   8DB437 AFF7448B      LEA ESI,DWORD PTR DS:[EDI+ESI+8B44F7AF]
13BE1DAB   8B7D FC              MOV EDI,DWORD PTR SS:[EBP-4]
13BE1DAE   33FA                 XOR EDI,EDX
13BE1DB0   C1C6 0C              ROL ESI,0C
13BE1DB3   03F2                 ADD ESI,EDX
13BE1DB5   23FE                 AND EDI,ESI
13BE1DB7   337D FC              XOR EDI,DWORD PTR SS:[EBP-4]
13BE1DBA   0378 28              ADD EDI,DWORD PTR DS:[EAX+28]
13BE1DBD   8DBC1F B15BFFFF      LEA EDI,DWORD PTR DS:[EDI+EBX+FFFF5BB1]
13BE1DC4   C1CF 0F              ROR EDI,0F
13BE1DC7   03FE                 ADD EDI,ESI
13BE1DC9   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE1DCC   8BDE                 MOV EBX,ESI
13BE1DCE   33DA                 XOR EBX,EDX
13BE1DD0   23DF                 AND EBX,EDI
13BE1DD2   8B7D FC              MOV EDI,DWORD PTR SS:[EBP-4]
13BE1DD5   33DA                 XOR EBX,EDX
13BE1DD7   0358 2C              ADD EBX,DWORD PTR DS:[EAX+2C]
13BE1DDA   8DBC3B BED75C89      LEA EDI,DWORD PTR DS:[EBX+EDI+895CD7BE]
13BE1DE1   C1CF 0A              ROR EDI,0A
13BE1DE4   037D F4              ADD EDI,DWORD PTR SS:[EBP-C]
13BE1DE7   897D FC              MOV DWORD PTR SS:[EBP-4],EDI
13BE1DEA   8BFE                 MOV EDI,ESI
13BE1DEC   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1DEF   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1DF2   237D FC              AND EDI,DWORD PTR SS:[EBP-4]
13BE1DF5   33FE                 XOR EDI,ESI
13BE1DF7   0378 30              ADD EDI,DWORD PTR DS:[EAX+30]
13BE1DFA   8D9417 2211906B      LEA EDX,DWORD PTR DS:[EDI+EDX+6B901122]
13BE1E01   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE1E04   337D FC              XOR EDI,DWORD PTR SS:[EBP-4]
13BE1E07   C1C2 07              ROL EDX,7
13BE1E0A   0355 FC              ADD EDX,DWORD PTR SS:[EBP-4]
13BE1E0D   23FA                 AND EDI,EDX
13BE1E0F   337D F4              XOR EDI,DWORD PTR SS:[EBP-C]
13BE1E12   33DA                 XOR EBX,EDX
13BE1E14   0378 34              ADD EDI,DWORD PTR DS:[EAX+34]
13BE1E17   8DB437 937198FD      LEA ESI,DWORD PTR DS:[EDI+ESI+FD987193]
13BE1E1E   8B78 38              MOV EDI,DWORD PTR DS:[EAX+38]
13BE1E21   C1C6 0C              ROL ESI,0C
13BE1E24   03F2                 ADD ESI,EDX
13BE1E26   23DE                 AND EBX,ESI
13BE1E28   335D FC              XOR EBX,DWORD PTR SS:[EBP-4]
13BE1E2B   8975 F8              MOV DWORD PTR SS:[EBP-8],ESI
13BE1E2E   03DF                 ADD EBX,EDI
13BE1E30   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE1E33   8DBC3B 8E4379A6      LEA EDI,DWORD PTR DS:[EBX+EDI+A679438E]
13BE1E3A   8B58 3C              MOV EBX,DWORD PTR DS:[EAX+3C]
13BE1E3D   C1CF 0F              ROR EDI,0F
13BE1E40   03FE                 ADD EDI,ESI
13BE1E42   33F2                 XOR ESI,EDX
13BE1E44   23F7                 AND ESI,EDI
13BE1E46   33F2                 XOR ESI,EDX
13BE1E48   03F3                 ADD ESI,EBX
13BE1E4A   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1E4D   8DB41E 2108B449      LEA ESI,DWORD PTR DS:[ESI+EBX+49B40821]
13BE1E54   C1CE 0A              ROR ESI,0A
13BE1E57   03F7                 ADD ESI,EDI
13BE1E59   8BDF                 MOV EBX,EDI
13BE1E5B   33DE                 XOR EBX,ESI
13BE1E5D   235D F8              AND EBX,DWORD PTR SS:[EBP-8]
13BE1E60   8975 FC              MOV DWORD PTR SS:[EBP-4],ESI
13BE1E63   33DF                 XOR EBX,EDI
13BE1E65   0358 04              ADD EBX,DWORD PTR DS:[EAX+4]
13BE1E68   8D9413 62251EF6      LEA EDX,DWORD PTR DS:[EBX+EDX+F61E2562]
13BE1E6F   C1C2 05              ROL EDX,5
13BE1E72   03D6                 ADD EDX,ESI
13BE1E74   33F2                 XOR ESI,EDX
13BE1E76   23F7                 AND ESI,EDI
13BE1E78   3375 FC              XOR ESI,DWORD PTR SS:[EBP-4]
13BE1E7B   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE1E7E   0370 18              ADD ESI,DWORD PTR DS:[EAX+18]
13BE1E81   8DB41E 40B340C0      LEA ESI,DWORD PTR DS:[ESI+EBX+C040B340]
13BE1E88   C1C6 09              ROL ESI,9
13BE1E8B   03F2                 ADD ESI,EDX
13BE1E8D   8975 F8              MOV DWORD PTR SS:[EBP-8],ESI
13BE1E90   33F2                 XOR ESI,EDX
13BE1E92   2375 FC              AND ESI,DWORD PTR SS:[EBP-4]
13BE1E95   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1E98   33F2                 XOR ESI,EDX
13BE1E9A   0370 2C              ADD ESI,DWORD PTR DS:[EAX+2C]
13BE1E9D   8DBC3E 515A5E26      LEA EDI,DWORD PTR DS:[ESI+EDI+265E5A51]
13BE1EA4   8B75 F8              MOV ESI,DWORD PTR SS:[EBP-8]
13BE1EA7   C1C7 0E              ROL EDI,0E
13BE1EAA   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE1EAD   33F7                 XOR ESI,EDI
13BE1EAF   23F2                 AND ESI,EDX
13BE1EB1   3375 F8              XOR ESI,DWORD PTR SS:[EBP-8]
13BE1EB4   0330                 ADD ESI,DWORD PTR DS:[EAX]
13BE1EB6   8DB41E AAC7B6E9      LEA ESI,DWORD PTR DS:[ESI+EBX+E9B6C7AA]
13BE1EBD   C1CE 0C              ROR ESI,0C
13BE1EC0   03F7                 ADD ESI,EDI
13BE1EC2   8975 FC              MOV DWORD PTR SS:[EBP-4],ESI
13BE1EC5   8BDF                 MOV EBX,EDI
13BE1EC7   33DE                 XOR EBX,ESI
13BE1EC9   235D F8              AND EBX,DWORD PTR SS:[EBP-8]
13BE1ECC   33DF                 XOR EBX,EDI
13BE1ECE   0358 14              ADD EBX,DWORD PTR DS:[EAX+14]
13BE1ED1   8D9413 5D102FD6      LEA EDX,DWORD PTR DS:[EBX+EDX+D62F105D]
13BE1ED8   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE1EDB   C1C2 05              ROL EDX,5
13BE1EDE   03D6                 ADD EDX,ESI
13BE1EE0   33F2                 XOR ESI,EDX
13BE1EE2   23F7                 AND ESI,EDI
13BE1EE4   3375 FC              XOR ESI,DWORD PTR SS:[EBP-4]
13BE1EE7   0370 28              ADD ESI,DWORD PTR DS:[EAX+28]
13BE1EEA   8DB41E 53144402      LEA ESI,DWORD PTR DS:[ESI+EBX+2441453]
13BE1EF1   C1C6 09              ROL ESI,9
13BE1EF4   03F2                 ADD ESI,EDX
13BE1EF6   8975 F8              MOV DWORD PTR SS:[EBP-8],ESI
13BE1EF9   33F2                 XOR ESI,EDX
13BE1EFB   2375 FC              AND ESI,DWORD PTR SS:[EBP-4]
13BE1EFE   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1F01   33F2                 XOR ESI,EDX
13BE1F03   0370 3C              ADD ESI,DWORD PTR DS:[EAX+3C]
13BE1F06   8DBC3E 81E6A1D8      LEA EDI,DWORD PTR DS:[ESI+EDI+D8A1E681]
13BE1F0D   8B75 F8              MOV ESI,DWORD PTR SS:[EBP-8]
13BE1F10   C1C7 0E              ROL EDI,0E
13BE1F13   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE1F16   33F7                 XOR ESI,EDI
13BE1F18   23F2                 AND ESI,EDX
13BE1F1A   3375 F8              XOR ESI,DWORD PTR SS:[EBP-8]
13BE1F1D   0370 10              ADD ESI,DWORD PTR DS:[EAX+10]
13BE1F20   8DB41E C8FBD3E7      LEA ESI,DWORD PTR DS:[ESI+EBX+E7D3FBC8]
13BE1F27   C1CE 0C              ROR ESI,0C
13BE1F2A   03F7                 ADD ESI,EDI
13BE1F2C   8BDF                 MOV EBX,EDI
13BE1F2E   33DE                 XOR EBX,ESI
13BE1F30   235D F8              AND EBX,DWORD PTR SS:[EBP-8]
13BE1F33   8975 FC              MOV DWORD PTR SS:[EBP-4],ESI
13BE1F36   33DF                 XOR EBX,EDI
13BE1F38   0358 24              ADD EBX,DWORD PTR DS:[EAX+24]
13BE1F3B   8D9413 E6CDE121      LEA EDX,DWORD PTR DS:[EBX+EDX+21E1CDE6]
13BE1F42   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE1F45   C1C2 05              ROL EDX,5
13BE1F48   03D6                 ADD EDX,ESI
13BE1F4A   33F2                 XOR ESI,EDX
13BE1F4C   23F7                 AND ESI,EDI
13BE1F4E   3375 FC              XOR ESI,DWORD PTR SS:[EBP-4]
13BE1F51   0370 38              ADD ESI,DWORD PTR DS:[EAX+38]
13BE1F54   8DB41E D60737C3      LEA ESI,DWORD PTR DS:[ESI+EBX+C33707D6]
13BE1F5B   C1C6 09              ROL ESI,9
13BE1F5E   03F2                 ADD ESI,EDX
13BE1F60   8975 F8              MOV DWORD PTR SS:[EBP-8],ESI
13BE1F63   33F2                 XOR ESI,EDX
13BE1F65   2375 FC              AND ESI,DWORD PTR SS:[EBP-4]
13BE1F68   33F2                 XOR ESI,EDX
13BE1F6A   0370 0C              ADD ESI,DWORD PTR DS:[EAX+C]
13BE1F6D   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1F70   8DBC3E 870DD5F4      LEA EDI,DWORD PTR DS:[ESI+EDI+F4D50D87]
13BE1F77   8B75 F8              MOV ESI,DWORD PTR SS:[EBP-8]
13BE1F7A   C1C7 0E              ROL EDI,0E
13BE1F7D   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE1F80   33F7                 XOR ESI,EDI
13BE1F82   23F2                 AND ESI,EDX
13BE1F84   3375 F8              XOR ESI,DWORD PTR SS:[EBP-8]
13BE1F87   0370 20              ADD ESI,DWORD PTR DS:[EAX+20]
13BE1F8A   8DB41E ED145A45      LEA ESI,DWORD PTR DS:[ESI+EBX+455A14ED]
13BE1F91   C1CE 0C              ROR ESI,0C
13BE1F94   03F7                 ADD ESI,EDI
13BE1F96   8BDF                 MOV EBX,EDI
13BE1F98   33DE                 XOR EBX,ESI
13BE1F9A   235D F8              AND EBX,DWORD PTR SS:[EBP-8]
13BE1F9D   8975 FC              MOV DWORD PTR SS:[EBP-4],ESI
13BE1FA0   33DF                 XOR EBX,EDI
13BE1FA2   0358 34              ADD EBX,DWORD PTR DS:[EAX+34]
13BE1FA5   8D9413 05E9E3A9      LEA EDX,DWORD PTR DS:[EBX+EDX+A9E3E905]
13BE1FAC   8BDE                 MOV EBX,ESI
13BE1FAE   C1C2 05              ROL EDX,5
13BE1FB1   03D6                 ADD EDX,ESI
13BE1FB3   33DA                 XOR EBX,EDX
13BE1FB5   23DF                 AND EBX,EDI
13BE1FB7   33DE                 XOR EBX,ESI
13BE1FB9   8B70 08              MOV ESI,DWORD PTR DS:[EAX+8]
13BE1FBC   03DE                 ADD EBX,ESI
13BE1FBE   8975 E8              MOV DWORD PTR SS:[EBP-18],ESI
13BE1FC1   8B75 F8              MOV ESI,DWORD PTR SS:[EBP-8]
13BE1FC4   8DB433 F8A3EFFC      LEA ESI,DWORD PTR DS:[EBX+ESI+FCEFA3F8]
13BE1FCB   C1C6 09              ROL ESI,9
13BE1FCE   03F2                 ADD ESI,EDX
13BE1FD0   8975 F8              MOV DWORD PTR SS:[EBP-8],ESI
13BE1FD3   33F2                 XOR ESI,EDX
13BE1FD5   2375 FC              AND ESI,DWORD PTR SS:[EBP-4]
13BE1FD8   8B5D FC              MOV EBX,DWORD PTR SS:[EBP-4]
13BE1FDB   33F2                 XOR ESI,EDX
13BE1FDD   0370 1C              ADD ESI,DWORD PTR DS:[EAX+1C]
13BE1FE0   8DBC3E D9026F67      LEA EDI,DWORD PTR DS:[ESI+EDI+676F02D9]
13BE1FE7   8B75 F8              MOV ESI,DWORD PTR SS:[EBP-8]
13BE1FEA   C1C7 0E              ROL EDI,0E
13BE1FED   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE1FF0   33F7                 XOR ESI,EDI
13BE1FF2   8975 F0              MOV DWORD PTR SS:[EBP-10],ESI
13BE1FF5   23F2                 AND ESI,EDX
13BE1FF7   3375 F8              XOR ESI,DWORD PTR SS:[EBP-8]
13BE1FFA   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE1FFD   0370 30              ADD ESI,DWORD PTR DS:[EAX+30]
13BE2000   8DB41E 8A4C2A8D      LEA ESI,DWORD PTR DS:[ESI+EBX+8D2A4C8A]
13BE2007   8B58 14              MOV EBX,DWORD PTR DS:[EAX+14]
13BE200A   C1CE 0C              ROR ESI,0C
13BE200D   03F7                 ADD ESI,EDI
13BE200F   8B7D F0              MOV EDI,DWORD PTR SS:[EBP-10]
13BE2012   33FE                 XOR EDI,ESI
13BE2014   03FB                 ADD EDI,EBX
13BE2016   8D9417 4239FAFF      LEA EDX,DWORD PTR DS:[EDI+EDX+FFFA3942]
13BE201D   8B78 20              MOV EDI,DWORD PTR DS:[EAX+20]
13BE2020   895D E0              MOV DWORD PTR SS:[EBP-20],EBX
13BE2023   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE2026   33DE                 XOR EBX,ESI
13BE2028   C1C2 04              ROL EDX,4
13BE202B   03D6                 ADD EDX,ESI
13BE202D   33DA                 XOR EBX,EDX
13BE202F   03DF                 ADD EBX,EDI
13BE2031   897D D0              MOV DWORD PTR SS:[EBP-30],EDI
13BE2034   8B7D F8              MOV EDI,DWORD PTR SS:[EBP-8]
13BE2037   8DBC3B 81F67187      LEA EDI,DWORD PTR DS:[EBX+EDI+8771F681]
13BE203E   C1C7 0B              ROL EDI,0B
13BE2041   03FA                 ADD EDI,EDX
13BE2043   8BDF                 MOV EBX,EDI
13BE2045   897D F8              MOV DWORD PTR SS:[EBP-8],EDI
13BE2048   8B78 2C              MOV EDI,DWORD PTR DS:[EAX+2C]
13BE204B   33DE                 XOR EBX,ESI
13BE204D   33DA                 XOR EBX,EDX
13BE204F   897D C0              MOV DWORD PTR SS:[EBP-40],EDI
13BE2052   03DF                 ADD EBX,EDI
13BE2054   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE2057   8DBC3B 22619D6D      LEA EDI,DWORD PTR DS:[EBX+EDI+6D9D6122]
13BE205E   C1C7 10              ROL EDI,10
13BE2061   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE2064   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE2067   33DF                 XOR EBX,EDI
13BE2069   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE206C   8B78 38              MOV EDI,DWORD PTR DS:[EAX+38]
13BE206F   895D F0              MOV DWORD PTR SS:[EBP-10],EBX
13BE2072   33DA                 XOR EBX,EDX
13BE2074   03DF                 ADD EBX,EDI
13BE2076   8DB433 0C38E5FD      LEA ESI,DWORD PTR DS:[EBX+ESI+FDE5380C]
13BE207D   8B58 04              MOV EBX,DWORD PTR DS:[EAX+4]
13BE2080   897D E4              MOV DWORD PTR SS:[EBP-1C],EDI
13BE2083   8B7D F0              MOV EDI,DWORD PTR SS:[EBP-10]
13BE2086   C1CE 09              ROR ESI,9
13BE2089   0375 F4              ADD ESI,DWORD PTR SS:[EBP-C]
13BE208C   895D D4              MOV DWORD PTR SS:[EBP-2C],EBX
13BE208F   33FE                 XOR EDI,ESI
13BE2091   03FB                 ADD EDI,EBX
13BE2093   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE2096   8D9417 44EABEA4      LEA EDX,DWORD PTR DS:[EDI+EDX+A4BEEA44]
13BE209D   8B78 10              MOV EDI,DWORD PTR DS:[EAX+10]
13BE20A0   33DE                 XOR EBX,ESI
13BE20A2   897D C4              MOV DWORD PTR SS:[EBP-3C],EDI
13BE20A5   C1C2 04              ROL EDX,4
13BE20A8   03D6                 ADD EDX,ESI
13BE20AA   33DA                 XOR EBX,EDX
13BE20AC   03DF                 ADD EBX,EDI
13BE20AE   8B7D F8              MOV EDI,DWORD PTR SS:[EBP-8]
13BE20B1   8DBC3B A9CFDE4B      LEA EDI,DWORD PTR DS:[EBX+EDI+4BDECFA9]
13BE20B8   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE20BB   C1C7 0B              ROL EDI,0B
13BE20BE   03FA                 ADD EDI,EDX
13BE20C0   897D F8              MOV DWORD PTR SS:[EBP-8],EDI
13BE20C3   33FE                 XOR EDI,ESI
13BE20C5   33FA                 XOR EDI,EDX
13BE20C7   0378 1C              ADD EDI,DWORD PTR DS:[EAX+1C]
13BE20CA   8DBC1F 604BBBF6      LEA EDI,DWORD PTR DS:[EDI+EBX+F6BB4B60]
13BE20D1   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE20D4   C1C7 10              ROL EDI,10
13BE20D7   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE20DA   33DF                 XOR EBX,EDI
13BE20DC   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE20DF   8B78 28              MOV EDI,DWORD PTR DS:[EAX+28]
13BE20E2   895D F0              MOV DWORD PTR SS:[EBP-10],EBX
13BE20E5   33DA                 XOR EBX,EDX
13BE20E7   03DF                 ADD EBX,EDI
13BE20E9   8DB433 70BCBFBE      LEA ESI,DWORD PTR DS:[EBX+ESI+BEBFBC70]
13BE20F0   8B58 34              MOV EBX,DWORD PTR DS:[EAX+34]
13BE20F3   897D D8              MOV DWORD PTR SS:[EBP-28],EDI
13BE20F6   8B7D F0              MOV EDI,DWORD PTR SS:[EBP-10]
13BE20F9   C1CE 09              ROR ESI,9
13BE20FC   0375 F4              ADD ESI,DWORD PTR SS:[EBP-C]
13BE20FF   895D C8              MOV DWORD PTR SS:[EBP-38],EBX
13BE2102   33FE                 XOR EDI,ESI
13BE2104   03FB                 ADD EDI,EBX
13BE2106   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE2109   8D9417 C67E9B28      LEA EDX,DWORD PTR DS:[EDI+EDX+289B7EC6]
13BE2110   8B38                 MOV EDI,DWORD PTR DS:[EAX]
13BE2112   33DE                 XOR EBX,ESI
13BE2114   C1C2 04              ROL EDX,4
13BE2117   03D6                 ADD EDX,ESI
13BE2119   33DA                 XOR EBX,EDX
13BE211B   03DF                 ADD EBX,EDI
13BE211D   897D FC              MOV DWORD PTR SS:[EBP-4],EDI
13BE2120   8B7D F8              MOV EDI,DWORD PTR SS:[EBP-8]
13BE2123   8DBC3B FA27A1EA      LEA EDI,DWORD PTR DS:[EBX+EDI+EAA127FA]
13BE212A   C1C7 0B              ROL EDI,0B
13BE212D   03FA                 ADD EDI,EDX
13BE212F   8BDF                 MOV EBX,EDI
13BE2131   897D F8              MOV DWORD PTR SS:[EBP-8],EDI
13BE2134   8B78 0C              MOV EDI,DWORD PTR DS:[EAX+C]
13BE2137   33DE                 XOR EBX,ESI
13BE2139   33DA                 XOR EBX,EDX
13BE213B   03DF                 ADD EBX,EDI
13BE213D   897D DC              MOV DWORD PTR SS:[EBP-24],EDI
13BE2140   8B7D F4              MOV EDI,DWORD PTR SS:[EBP-C]
13BE2143   8DBC3B 8530EFD4      LEA EDI,DWORD PTR DS:[EBX+EDI+D4EF3085]
13BE214A   8B5D F8              MOV EBX,DWORD PTR SS:[EBP-8]
13BE214D   C1C7 10              ROL EDI,10
13BE2150   037D F8              ADD EDI,DWORD PTR SS:[EBP-8]
13BE2153   33DF                 XOR EBX,EDI
13BE2155   897D F4              MOV DWORD PTR SS:[EBP-C],EDI
13BE2158   895D F0              MOV DWORD PTR SS:[EBP-10],EBX
13BE215B   33DA                 XOR EBX,EDX
13BE215D   8B78 18              MOV EDI,DWORD PTR DS:[EAX+18]
13BE2160   03DF                 ADD EBX,EDI
13BE2162   8DB433 051D8804      LEA ESI,DWORD PTR DS:[EBX+ESI+4881D05]
13BE2169   8B58 24              MOV EBX,DWORD PTR DS:[EAX+24]
13BE216C   895D BC              MOV DWORD PTR SS:[EBP-44],EBX
13BE216F   C1CE 09              ROR ESI,9
13BE2172   0375 F4              ADD ESI,DWORD PTR SS:[EBP-C]
13BE2175   897D CC              MOV DWORD PTR SS:[EBP-34],EDI
13BE2178   8B7D F0              MOV EDI,DWORD PTR SS:[EBP-10]
13BE217B   33FE                 XOR EDI,ESI
13BE217D   03FB                 ADD EDI,EBX
13BE217F   8B5D F4              MOV EBX,DWORD PTR SS:[EBP-C]
13BE2182   33DE                 XOR EBX,ESI
13BE2184   8D9417 39D0D4D9      LEA EDX,DWORD PTR DS:[EDI+EDX+D9D4D039]
13BE218B   8B78 30              MOV EDI,DWORD PTR DS:[EAX+30]
13BE218E   8B40 3C              MOV EAX,DWORD PTR DS:[EAX+3C]
13BE2191   C1C2 04              ROL EDX,4
13BE2194   03D6                 ADD EDX,ESI
13BE2196   33DA                 XOR EBX,EDX
13BE2198   03DF                 ADD EBX,EDI
13BE219A   897D F0              MOV DWORD PTR SS:[EBP-10],EDI
13BE219D   8B7D F8              MOV EDI,DWORD PTR SS:[EBP-8]
13BE21A0   8DBC3B E599DBE6      LEA EDI,DWORD PTR DS:[EBX+EDI+E6DB99E5]
13BE21A7   C1C7 0B              ROL EDI,0B
13BE21AA   03FA                 ADD EDI,EDX
13BE21AC   8BDF                 MOV EBX,EDI
13BE21AE   33DE                 XOR EBX,ESI
13BE21B0   33DA                 XOR EBX,EDX
13BE21B2   03D8                 ADD EBX,EAX
13BE21B4   8945 F8              MOV DWORD PTR SS:[EBP-8],EAX
13BE21B7   8B45 F4              MOV EAX,DWORD PTR SS:[EBP-C]
13BE21BA   8D8403 F87CA21F      LEA EAX,DWORD PTR DS:[EBX+EAX+1FA27CF8]
13BE21C1   C1C0 10              ROL EAX,10
13BE21C4   03C7                 ADD EAX,EDI
13BE21C6   8BDF                 MOV EBX,EDI
13BE21C8   33D8                 XOR EBX,EAX
13BE21CA   33DA                 XOR EBX,EDX
13BE21CC   035D E8              ADD EBX,DWORD PTR SS:[EBP-18]
13BE21CF   8DB433 6556ACC4      LEA ESI,DWORD PTR DS:[EBX+ESI+C4AC5665]
13BE21D6   C1CE 09              ROR ESI,9
13BE21D9   03F0                 ADD ESI,EAX
13BE21DB   8BDF                 MOV EBX,EDI
13BE21DD   F7D3                 NOT EBX
13BE21DF   0BDE                 OR EBX,ESI
13BE21E1   33D8                 XOR EBX,EAX
13BE21E3   035D FC              ADD EBX,DWORD PTR SS:[EBP-4]
13BE21E6   8D9413 442229F4      LEA EDX,DWORD PTR DS:[EBX+EDX+F4292244]
13BE21ED   C1C2 06              ROL EDX,6
13BE21F0   03D6                 ADD EDX,ESI
13BE21F2   8BD8                 MOV EBX,EAX
13BE21F4   F7D3                 NOT EBX
13BE21F6   0BDA                 OR EBX,EDX
13BE21F8   33DE                 XOR EBX,ESI
13BE21FA   035D EC              ADD EBX,DWORD PTR SS:[EBP-14]
13BE21FD   8DBC3B 97FF2A43      LEA EDI,DWORD PTR DS:[EBX+EDI+432AFF97]
13BE2204   C1C7 0A              ROL EDI,0A
13BE2207   03FA                 ADD EDI,EDX
13BE2209   8BDE                 MOV EBX,ESI
13BE220B   F7D3                 NOT EBX
13BE220D   0BDF                 OR EBX,EDI
13BE220F   33DA                 XOR EBX,EDX
13BE2211   035D E4              ADD EBX,DWORD PTR SS:[EBP-1C]
13BE2214   8D8403 A72394AB      LEA EAX,DWORD PTR DS:[EBX+EAX+AB9423A7]
13BE221B   C1C0 0F              ROL EAX,0F
13BE221E   03C7                 ADD EAX,EDI
13BE2220   8BDA                 MOV EBX,EDX
13BE2222   F7D3                 NOT EBX
13BE2224   0BD8                 OR EBX,EAX
13BE2226   33DF                 XOR EBX,EDI
13BE2228   035D E0              ADD EBX,DWORD PTR SS:[EBP-20]
13BE222B   8DB433 39A093FC      LEA ESI,DWORD PTR DS:[EBX+ESI+FC93A039]
13BE2232   C1CE 0B              ROR ESI,0B
13BE2235   8BDF                 MOV EBX,EDI
13BE2237   F7D3                 NOT EBX
13BE2239   03F0                 ADD ESI,EAX
13BE223B   0BDE                 OR EBX,ESI
13BE223D   33D8                 XOR EBX,EAX
13BE223F   035D F0              ADD EBX,DWORD PTR SS:[EBP-10]
13BE2242   8D9413 C3595B65      LEA EDX,DWORD PTR DS:[EBX+EDX+655B59C3]
13BE2249   C1C2 06              ROL EDX,6
13BE224C   03D6                 ADD EDX,ESI
13BE224E   8BD8                 MOV EBX,EAX
13BE2250   F7D3                 NOT EBX
13BE2252   0BDA                 OR EBX,EDX
13BE2254   33DE                 XOR EBX,ESI
13BE2256   035D DC              ADD EBX,DWORD PTR SS:[EBP-24]
13BE2259   8DBC3B 92CC0C8F      LEA EDI,DWORD PTR DS:[EBX+EDI+8F0CCC92]
13BE2260   C1C7 0A              ROL EDI,0A
13BE2263   03FA                 ADD EDI,EDX
13BE2265   8BDE                 MOV EBX,ESI
13BE2267   F7D3                 NOT EBX
13BE2269   0BDF                 OR EBX,EDI
13BE226B   33DA                 XOR EBX,EDX
13BE226D   035D D8              ADD EBX,DWORD PTR SS:[EBP-28]
13BE2270   8D8403 7DF4EFFF      LEA EAX,DWORD PTR DS:[EBX+EAX+FFEFF47D]
13BE2277   C1C0 0F              ROL EAX,0F
13BE227A   03C7                 ADD EAX,EDI
13BE227C   8BDA                 MOV EBX,EDX
13BE227E   F7D3                 NOT EBX
13BE2280   0BD8                 OR EBX,EAX
13BE2282   33DF                 XOR EBX,EDI
13BE2284   035D D4              ADD EBX,DWORD PTR SS:[EBP-2C]
13BE2287   8DB433 D15D8485      LEA ESI,DWORD PTR DS:[EBX+ESI+85845DD1]
13BE228E   C1CE 0B              ROR ESI,0B
13BE2291   03F0                 ADD ESI,EAX
13BE2293   8BDF                 MOV EBX,EDI
13BE2295   F7D3                 NOT EBX
13BE2297   0BDE                 OR EBX,ESI
13BE2299   33D8                 XOR EBX,EAX
13BE229B   035D D0              ADD EBX,DWORD PTR SS:[EBP-30]
13BE229E   8D9413 4F7EA86F      LEA EDX,DWORD PTR DS:[EBX+EDX+6FA87E4F]
13BE22A5   C1C2 06              ROL EDX,6
13BE22A8   03D6                 ADD EDX,ESI
13BE22AA   8BD8                 MOV EBX,EAX
13BE22AC   F7D3                 NOT EBX
13BE22AE   0BDA                 OR EBX,EDX
13BE22B0   33DE                 XOR EBX,ESI
13BE22B2   035D F8              ADD EBX,DWORD PTR SS:[EBP-8]
13BE22B5   8DBC3B E0E62CFE      LEA EDI,DWORD PTR DS:[EBX+EDI+FE2CE6E0]
13BE22BC   C1C7 0A              ROL EDI,0A
13BE22BF   03FA                 ADD EDI,EDX
13BE22C1   8BDE                 MOV EBX,ESI
13BE22C3   F7D3                 NOT EBX
13BE22C5   0BDF                 OR EBX,EDI
13BE22C7   33DA                 XOR EBX,EDX
13BE22C9   035D CC              ADD EBX,DWORD PTR SS:[EBP-34]
13BE22CC   8D8403 144301A3      LEA EAX,DWORD PTR DS:[EBX+EAX+A3014314]
13BE22D3   C1C0 0F              ROL EAX,0F
13BE22D6   03C7                 ADD EAX,EDI
13BE22D8   8BDA                 MOV EBX,EDX
13BE22DA   F7D3                 NOT EBX
13BE22DC   0BD8                 OR EBX,EAX
13BE22DE   33DF                 XOR EBX,EDI
13BE22E0   035D C8              ADD EBX,DWORD PTR SS:[EBP-38]
13BE22E3   8DB433 A111084E      LEA ESI,DWORD PTR DS:[EBX+ESI+4E0811A1]
13BE22EA   C1CE 0B              ROR ESI,0B
13BE22ED   03F0                 ADD ESI,EAX
13BE22EF   8BDF                 MOV EBX,EDI
13BE22F1   F7D3                 NOT EBX
13BE22F3   0BDE                 OR EBX,ESI
13BE22F5   33D8                 XOR EBX,EAX
13BE22F7   035D C4              ADD EBX,DWORD PTR SS:[EBP-3C]
13BE22FA   8D9413 827E53F7      LEA EDX,DWORD PTR DS:[EBX+EDX+F7537E82]
13BE2301   C1C2 06              ROL EDX,6
13BE2304   03D6                 ADD EDX,ESI
13BE2306   8BD8                 MOV EBX,EAX
13BE2308   F7D3                 NOT EBX
13BE230A   0BDA                 OR EBX,EDX
13BE230C   33DE                 XOR EBX,ESI
13BE230E   035D C0              ADD EBX,DWORD PTR SS:[EBP-40]
13BE2311   8DBC3B 35F23ABD      LEA EDI,DWORD PTR DS:[EBX+EDI+BD3AF235]
13BE2318   C1C7 0A              ROL EDI,0A
13BE231B   03FA                 ADD EDI,EDX
13BE231D   8BDE                 MOV EBX,ESI
13BE231F   F7D3                 NOT EBX
13BE2321   0BDF                 OR EBX,EDI
13BE2323   33DA                 XOR EBX,EDX
13BE2325   035D E8              ADD EBX,DWORD PTR SS:[EBP-18]
13BE2328   8D8403 BBD2D72A      LEA EAX,DWORD PTR DS:[EBX+EAX+2AD7D2BB]
13BE232F   C1C0 0F              ROL EAX,0F
13BE2332   03C7                 ADD EAX,EDI
13BE2334   8BDA                 MOV EBX,EDX
13BE2336   F7D3                 NOT EBX
13BE2338   0BD8                 OR EBX,EAX
13BE233A   33DF                 XOR EBX,EDI
13BE233C   035D BC              ADD EBX,DWORD PTR SS:[EBP-44]
13BE233F   8DB433 91D386EB      LEA ESI,DWORD PTR DS:[EBX+ESI+EB86D391]
13BE2346   8B19                 MOV EBX,DWORD PTR DS:[ECX]
13BE2348   03DA                 ADD EBX,EDX
13BE234A   8B51 04              MOV EDX,DWORD PTR DS:[ECX+4]
13BE234D   C1CE 0B              ROR ESI,0B
13BE2350   03F0                 ADD ESI,EAX
13BE2352   03D6                 ADD EDX,ESI
13BE2354   8951 04              MOV DWORD PTR DS:[ECX+4],EDX
13BE2357   8B51 08              MOV EDX,DWORD PTR DS:[ECX+8]
13BE235A   03D0                 ADD EDX,EAX
13BE235C   8B41 0C              MOV EAX,DWORD PTR DS:[ECX+C]
13BE235F   03C7                 ADD EAX,EDI
13BE2361   5F                   POP EDI
13BE2362   5E                   POP ESI
13BE2363   8919                 MOV DWORD PTR DS:[ECX],EBX
13BE2365   8951 08              MOV DWORD PTR DS:[ECX+8],EDX
13BE2368   8941 0C              MOV DWORD PTR DS:[ECX+C],EAX
13BE236B   5B                   POP EBX
13BE236C   C9                   LEAVE
13BE236D   C3                   RETN

Which is a short way of saying this is MD5Transform from the Source SDK.

I also found CRC32_ProcessBuffer as well for their encoding of the scan buffer results ( from MD5Transform )

The most interesting tidbit was this from scan gate 9

Code:

13BE8FB0  20 07 00 00 C5 07 00 00 AB 32 78 95               ..Å..«2x•

720 -> size of code
7C5 / 8 = iterations for decode function
957832AB = crc of scan code ( see CRC32_ProcessBuffer )

Now what they do is check their scan code to make sure it's not been tampered or they exit out and detect you.

Note they include all the relevant information to decode their scan data in each scan gate. You just have to find it and then decoding their functions is simple the plus side is you get a free crc to validate whether you properly decoded it or not.

For more information check tier1 in the sdk for checksum_md5 & checksum_crc.

18 Comments

GameOverlayUI (Render in any game that uses the steam overlay)

s0beit

Published on 02-22-2010 02:18 PM

Categories:

HI I have reversed the steam GameOverlayUI properly, rather than the clumsy method i used before in my MW2 hook. ... ...

15 Comments

Forums Upgraded to vBulletin 4.0

Absolution

Published on 02-10-2010 04:05 AM

I've upgraded the forums to vBulletin 4.0.

Some of you may be wondering why I would do such a thing. The old main site was based on a joomla+vbulletin bridge which was literally a huge pain in [my] the ass. And as such, I never updated. It was quite a broken system and just didn't work well. I also had security concerns with running joomla; they don't exactly have a good track record. It is als ...

17 Comments